METHOD OF CATHODE PROTECTION OF CASING STRINGS OF WELLS AND OIL-FIELD PIPELINES AGAINST CORROSION Russian patent published in 2017 - IPC C23F13/02 

FIELD: oil and gas industry.

SUBSTANCE: method includes drilling holes to a depth greater than the length of the corresponding anode grounding electrode, drilling each hole in the depth interval of anode grounding electrode, setting a carpet, after completion of drilling, immediately before lowering of anode grounding electrodes in a bore pit, pumping is carried out up to the upper carpet level of clay solution and current-conducting colmatage solution, lowering the anode grounding device, installing protective current on the casing string through a cathode protection station, controlling parameters of cathode protection on the corresponding cathode cable, at that the bore pits are drilled at a planned distance from the casing strings, the groups of wells with similar design parameters are determined according to respective resistances, and the wells with resistance parameters different from the groups of wells are determined, a corresponding common cathode cable connected to the cathode protection station and parallel to each of the casing strings is laid between each group of wells, and the wells with different resistances are provided with individual cathode cables with cathode protection station, in this case, the anode grounding electrodes are connected in parallel to a common anode cable which is connected to the cathode protection station, and parameters of cathode protection on the cathode cables are adjusted by protective current so that the variation of parameters from the mean value does not exceed 10%.

EFFECT: servicing cathode protection facilities with different electric protection characteristics and simplified adjustment of protection currents.

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